Sunday, June 12, 2011

I notice that the battery life of my phone can last longer when it is in GSM (2G) mode than WCDMA (3G) mode.

Here is a simple observation of its battery consumption pattern. I switched it to GSM mode (Settings > Wireless & networks > Mobile networks > Network Mode > GSM only) during day time, and switched it to WCDMA mode (Settings > Wireless & networks > Mobile networks > Network Mode > WCDMA only) before I slept, and switched it back to GSM mode again the next day. Along the whole period, there is no phone call.

Here is the battery consumption pattern I get:

and here is the same graph shown in landscape view:

It is very obvious that when the phone is on WCDMA mode, its battery consumed faster.

This is an HTC Incredible S upgraded to Gingerbread Android (version 2.3.3). I do notice that when it is in GSM mode, the signal is pretty stable (I can always get a full bar), and when it is in WCDMA mode, the signal is not that stable (there are frequent occasions of losing one bar or two bars). Probably the stability of the signal is one of the major factor in battery consumption.

Anyhow, it is a known fact that the phone will consume less battery when it is in GSM mode rather than WCDMA mode, and it is among the tweaking of battery saving apps such as Juice Defender.

4
comments:

Did you know that the speed of dialing when in WCDMA mode is also faster?I mean, it takes shorter time to hear that "toot-toot" sound. When in GSM mode, it always takes 3 to 4 seconds before hearing the toot sound.And also, in 3G mode, the *100# hotlink portal reacts faster.

WCDMA is also commonly known as UMTS. Below is quoted from Wikipedia:"Even with current technologies and low-band UMTS, telephony and data over UMTS is still more power intensive than on comparable GSM networks. Apple Inc. cited[9] UMTS power consumption as the reason that the first generation iPhone only supported EDGE. Their release of the iPhone 3G quotes talk time on UMTS as half that available when the handset is set to use GSM. Other manufacturers indicate different battery lifetime for UMTS mode compared to GSM mode as well. As battery and network technology improves, this issue is diminishing." - Source: http://en.wikipedia.org/wiki/Universal_Mobile_Telecommunications_System